U.S. Pat. No. 6,534,689—description defines a method of pyrolysis of the waste plastics leading to fuel production. To separate solid particles from liquids the cyclone uses high vehicle velocity and high inert gas temperature as a heat transfer carrier. This invention utilizes inert gas and hydrocarbon vapours as heating medium.
Patent P—380619—description defines a method and apparatus for catalytic depolymerization of polyolefinic waste plastics characterized by two reactors in which depolymerization takes place. There is one tank reactor and a second flow reactor operating in cooperation. Shredded plastic waste is first heated, melted, and pumped under the reaction medium surface. Later the plastic molten mass is dispersed in the reaction medium. The depolymerization process occurs in the presence of the catalyst. From the reactor bottom reacting mixture is pumped to the flow reactor in which it is heated up to 400° C. The reaction occurs under normal and negative pressure. Pressure in the reactor depends on the planned outcome for product properties. Inside the flow reactor depolymerization takes place. Gas and liquid mixture comes in to the tank reactor where it is split into gas and liquid fraction.
The liquid phase is heated up and melts incoming plastic feedstock. In the bottom reactor area the initial reaction takes place in 360° C. In the upper section, the split into gas and liquids takes place in around 400° C. Hydrocarbon vapours produced come thru the active, chemically-neutralizing filter and are condensed. The process is continuous.
Patent P—383709—description defines an apparatus and method for depolymerization of polyolefinic waste plastics, especially polyolefins, with removing reaction leftovers and residues. The apparatus includes a feeding conveyor, a pyrolysis reactor, and a discharging section characterized by a gas engaging stabilizer equipped with a mixer and working in close loop with at least one external pyrolysis reactor with screw or ribbon mixer and pipe that closes the loop. The depolymerization process is carried out in the presence of inert gas and characterized by a reactor with enforced dual flow in which on direction is used to discharge the reactor's residue.